The present invention relates to refuse dumping apparatus, and in particular, a dumping apparatus for semi-automated portable refuse containers of the size typically used in residential and light commercial applications.
A growing number of mass producible portable refuse receptacles in the United States and Europe has created a need for economical and reliable dumping apparatus for handling them. These receptacles are typically plastic carts of the "roll-out" or "wheeled" type with capacities of about 0.75 cubic meters. Dumping apparatus for receptacles of this type are preferably adaptable for use on existing refuse collection vehicles, many of which include roll bar dumping mechanisms for containers of commercial size with capacities of up to about 12.0 cubic meters. The vehicles carrying dumping mechanisms of commercial size vary in age and design, and dumping apparatus for roll-out carts must be compatible with the existing dumping mechanism on the vehicle to facilitate the unobstructed operation of either one of them.
Dumping apparatus for portable roll-out carts have been used and are in use on refuse collection vehicles. In particular, U.S. Pat. No. 3,804,277 of Brown et al. describes a dumping mechanism for a portable waste container having on one of its sides a lower cross bar and an upper downwardly directed recess. The dumping mechanism includes a rotatable face plate having an upper saddle that is adapted to fit inside of the recess and a lower movable hook for automatically engaging the lower cross bar as the face plate is rotated to lift and invert the receptable. The dumping mechanism of Brown et al. suffers from the disadvantage of requiring an elaborate linkage assembly to position the lower movable hook into engagement with the cross bar at the proper time during a dumping cycle to stabilize the receptacle as it is lifted and inverted to empty its contents.
U.S. Pat. No. 4,042,137 of Hughes et al. describes a dumping apparatus that includes a rotatable lift platform which is adapted to engage and invert a portable refuse container to empty its contents. The rotatable platform includes a fixed hook, which engages an upper horizontal locking bar on the container, and a hydraulic piston, which has a hook secured to its free end. The hydraulic piston moves the hook into a locking position on a lower locking bar upon the start of frame rotation and retracts the hook from the locking position upon completion of a dumping operation. The Hughes et al. dumping apparatus suffers from the disadvantage of requiring the use of a hydraulic piston and other associated linkage to secure the container to the dumping apparatus during a dumping operation.
U.S. Pat. Nos. 4,365,922 and 4,422,814 of Borders describe dumping mechanisms that lift and invert a portable refuse container. The former and latter patents describe respective side-loading and ground level dumping mechanisms. Each patent describes a dumping mechanism having a frame mounted on a drive shaft of a rotary actuator that is secured to a refuse collection vehicle. Hook levers pivotally mounted to the frame engage an abutment on the refuse container and lock it into position on the frame as the container is inverted during a dumping operation. The Borders dumping mechanisms also suffer from the disadvantage of requiring elaborate linkage assemblies to stabilize the container as it is inverted.
U.S. Pat. No. 4,479,751 of Wyman et al. describes a dumping apparatus that includes a compound linkage system that interconnects a hook member and a receiving member. The linkage system promotes a relative sliding movement that changes the distance between the hook and receiving members so that they are operable to engage the horizontal lock bars of a roll-out cart receptacle during a dumping cycle. The Wyman et al. dumping apparatus suffers from the disadvantage of requiring the compound linkage system to provide a positive locking slide mechanism to secure the waste cart receptacle to it.